More boring again

Jim Burr

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I know we just hit this, but using my Jet mini for 10-12" peppermills with a forstner bit is leaving me about an inch short in the middle. Would an auger bit work better? I bore half from the top and half from the bottom to equalize any deflection. I ordered an extension for my forstner bits, but would the auger do the same thing for boring out the core using the same method? Bit sizes are 1" and 1.25".
 
Because you are "meeting in the middle" I don't see any issues using an auger bit. There would be too much tear out if you were going all the way through in one pass. Always back out the bit once in a while to reduce heat and chip build up.
 
When I started making duck and game calls, I found that Forstner (style) bits were not the best thing for end grain drilling/boring on hard-hardwoods. I much prefer brad points. With those, you can easily add an extension for what you are trying to do. Augers will work but, if hand held they are very difficult to keep straight. BTW, spade bits are not bad if kept sharp and they tend to run cooler.
 
I tried a spade bit that was sharp and got a lot of abuse from it. I'm using a jacobs chuck in the tailstock, as it should be used, ;) at about 500 rpm. I'm wondering if the extension on the forstner will wander more or if the auger will be ok doing the half and half :huh:. Are brad points made in 1" and 1 5/8" sizes?
 
more boreing again

I use the extention with my forestner bits and they work pretty good.They recommend that for a 1" forestner bit to keep the speed around 200 rpm,if your lathe doesn't go that slow,then you just have to take you time and go slow,keeping the chips clear.I'v never had a spade bit that would go straight.
 
I use forstner bits and extensions when needed. I start by just letting the tip touch the wood and when it finds it's center I start drilling. Seems to work for me.

Here is a video of me drilling into the endgrain of hard bubinga. It is a 2" bit and the lathe is running at around 500 rpms.

Drilling endgrain
 
I tried a spade bit that was sharp and got a lot of abuse from it. I'm using a jacobs chuck in the tailstock, as it should be used, ;) at about 500 rpm. I'm wondering if the extension on the forstner will wander more or if the auger will be ok doing the half and half :huh:. Are brad points made in 1" and 1 5/8" sizes?

Yes, large brad points are made but they are costly.
Forstners, if used on end grain should run r-e-a-l r-e-a-l slowly. Forstners are not designed for end grain work.
Now, I'll qualify a bit. There are a number of Forstner 'style' hole saws on the market with different teeth and cutting abilities. My experience is with original Forstners and original Forstner style bits. I do not like for end grain, especially on hard-hardwoods.
Brad points rule.
 
Jim I got a set of these bits from MCLS but see they don't have them on there website anymore. That is to bad as with a extension these things are hefty and don't drift like the regular forstner bits do. They have carbide tips and a screw tip in the middle. Glad I got mine when I did. Haven't been able to find them anywhere else on the net.
 

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Already have Frank and they are slick. They cut real well and like I said don't wonder. Did this on some end grain black locust. That is about as hard as you can get without turning concrete.
 
Yes, large brad points are made but they are costly.
Forstners, if used on end grain should run r-e-a-l r-e-a-l slowly. Forstners are not designed for end grain work.
Now, I'll qualify a bit. There are a number of Forstner 'style' hole saws on the market with different teeth and cutting abilities. My experience is with original Forstners and original Forstner style bits. I do not like for end grain, especially on hard-hardwoods.
Brad points rule.

I never heard of "Forstner 'style' hole saws" Frank. I'm also not sure what you mean by "original Forstners and original Forstner style bits". Can you elaborate? It would be nice if you showed us a picture of what you are talking about.

As you can see in my video. I'm cutting into endgrain like butter into some really hard hardwood. And I'm using real Forstner bits that are correctly sharpened.

FYI Janka Hardness

Jim, They look like great bits
 
These are the bits I'm using...I think it was a HF set picked up about 10 yrs ago. I use a diamond hone on the cutting surface and get very thin ribbons that last for days. 500 rpm is as low as the Jet Mini will go. This bit is about
3" long, this mill is 11". You can see why my extension is in the mail :(
 

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I know we just hit this, but using my Jet mini for 10-12" peppermills with a forstner bit is leaving me about an inch short in the middle. Would an auger bit work better? I bore half from the top and half from the bottom to equalize any deflection. I ordered an extension for my forstner bits, but would the auger do the same thing for boring out the core using the same method? Bit sizes are 1" and 1.25".

Jim,
I'm going to caution you on using the JET mini for drilling... I drilled a lot of peppermills on mine, but I also went through two quill spindle bolts doing so.
I would suggest that you drill in steps if you are using the forstners. Drill at slow speed and back out often to clear the hole.. I have a bit set up permanently in an extension that will allow me to drill up to about 9 inches in one direction, then reverse to go in the other direction... I also have a smaller jacobs chuck that will take the shaft of the forstner and will extend pretty far into the blank. I can actually run the chuck into the mill. But I do almost all of my drilling now on the Jet 1442 which has a longer travel on the tailstock.

I drilled most of my peppermills with forstners, but on occasion I did use a spade bit... they need to be sharp and again clear the hole often.

Like Frank, I prefer spade bits to drill for my game calls.
 
I never heard of "Forstner 'style' hole saws" Frank. I'm also not sure what you mean by "original Forstners and original Forstner style bits". Can you elaborate? It would be nice if you showed us a picture of what you are talking about.

As you can see in my video. I'm cutting into endgrain like butter into some really hard hardwood. And I'm using real Forstner bits that are correctly sharpened.

FYI Janka Hardness

Jim, They look like great bits

Good question.
I was trying to be specific. The original Forstner and 'Forstner style' bits are the familiar sawtooth design. There are now several makes on the market that use a different concept and look very unlike the Forstner. I have no experience with any of these so cannot comment on how well, or poorly, any of them might perform.
 
BTW, I did some on-line research on the Forstner. All sources claim that the design of the cutter is such that it can be used on wood from any angle without consideration of grain orientation.
That is contrary to my experience and recommendations.
I find that they do poorly on end grain of hard-hardwoods. Jim has shown he does OK.
In my experience they burn and must be extracted every 1/2" or so to clear chips as they do not have a mechanism for removing chips as a brad point does.
I went through several 3/4" Forstners before switching, happily, to a brad point.
That's me. Good luck with yer technique.
 
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